川东—鄂西地区二叠纪生物礁成因类型及潜伏礁预测

Genetic types of Permian organic reefs and prediction of hidden reefs in the eastern Sichuan-western Hubei area

从相对海平面升降对礁生长发育控制的角度建立新的生物礁成因分类 (进积礁、并进礁和退积礁 ) ,据此描述川东—鄂西地区二叠纪生物礁的属性 ,认为该区进积礁和退积礁并存。根据礁体的进积和退积方向对潜伏礁进行预测 ,指出鄂西地区见天坝礁群的东南侧应该存在层位相当于长兴组三段的潜伏礁带 ,华蓥山—川东成礁带以西可能存在层位相当于长兴组三段顶的潜伏礁带。

The genetic classification of organic reefs (prograded reefs, collateral reefs and retrograded reefs) is established from the angle of the control of the relative sea level rise and fall on the growth and development of reefs and the attributes of Permian reefs in the eastern Sichuan western Hubei area are described on that basis. The authors propose the view of co existence of prograded reef and retrograded reefs in the area and predict hidden reefs according to the directions of progradation and retrogradation of reefs. They suggest that the horizon at the southeastern side of the Jiantianba reef cluster in western Hubei is equivalent to the hidden reef belt in the third member of the Changxing Formation, and that to the west of the Huaying eastern Sichuan reef forming belt there might exist a hidden reef belt which is stratigraphically equivalent to the top of the third member of the Changxing Formation.